The waters of the earth are contaminated in numerous ways. Rivers and streams are contaminated by industrial discharge, contaminated run off, contaminants leaching into groundwater aquifers, animal waste polluting rivers and There are a number of threats to drinking water: improperly disposed of chemicals; animal wastes; pesticides; human wastes; wastes injected deep underground; and naturally-occurring substances can all contaminate water supplies. Drinking water that is not properly treated or disinfected, or which travels through an improperly maintained distribution system, may also pose a health risk. In addition as demands for water have increased in cities, waste treatment plants and other facilities release their treated water to rivers and streams and that water is mixed with more pristine water. In California, they inject treated water into groundwater sources to recharge the aquifer.

The New York Times recently published an article highlighting the limitations of the Safe Drinking Water Act. First of all, only public water supplies (those that serve more than 25 individuals) are required to test their water. There are only 91 substances of concern under the clean water act. Private well owners need to monitor their own water quality. The substances of concern under the Safe Drinking Water Act are a series of metals and inorganic compounds, volatile organic compounds, organic compounds and herbicides and pesticides. It is virtually impossible to test for all known chemicals; there are not even good tests to find trace levels of some substances. Analysis costs money. Water purification and disinfection costs money and disinfection may introduce undesirable contaminants into the water. There are more than 57,400 water systems in this country that need to test their water monthly. The regulatory process is impacted by politics, which are in turn controlled by various interest groups, and limitations on knowledge, money and time.

An example would be the EPA experience when trying to lower the acceptable limit on arsenic in drinking water. EPA proposed lowering the acceptable arsenic limit in drinking water to five parts per billion from 10 parts per billion. Arsenic is difficult to remove from water without “wet chemistry” and cannot be filtered out. Water systems and industries that use arsenic complained, arguing that the science was uncertain and the chemical was expensive to remove. Regulators relented and the arsenic limit remained at 10 parts per billion.

Money and the limits of chemical analysis are not infinite. I view the basic list of primary and secondary contaminants as indicators that other related chemicals might be present. For example if you have traces of gasoline, then you would look for the additives to gasoline. Finding any traces of pesticides then a detailed analysis for pesticides and their break down products would be searched for. In order to target your analysis you need to know what to look for. The history of the land and source of the water is a good starting point to know what you are looking for. It really is not feasible to test for everything in environmental investigation or in medicine. The largest municipal water supply systems pull water from so many sources and mix it that exhaustive analysis would be prohibitive. Some municipal water supplies ignore everything but the letter of the law; others try to push for more purification facilities to clean the water further.

In all honesty, mixed source municipal water containing reprocessed water is not water I am entirely comfortable with drinking. Chemicals are a fact of modern life they exist in pharmaceuticals, household products, personal care products, plastics, pesticides, industrial chemicals, human and animal waste; they are in short, all around us. There are estimated to be over 80,000 artificial chemicals in the world today. The structural diversity is enormous and it is not known which of these substances might adversely affect living things in subtle ways. Having worked for the EPA in the pre-manufacturing notice section I know testing for new chemicals is for gross and acute impact, subtle impact is very difficult to identify or predict. However, one thing is certain the growing class of known endocrine disrupting chemicals can disturb a staggering range of hormonal processes. Like natural hormones, some EDCs bind directly with hormone receptors.

When I purchased my home, one of my contingencies was water quality. The house sits on one of the most productive aquifers in Virginia and draws its water from a private well. I had the right to exit the purchase if the water quality was either unacceptable to me or did not meet US EPA Safe Drinking Water Standards. All we could negotiate was 12 day contingency period and in reality I had less time than that. The power needed to be turned on to operate the water pump, the and water tanks drained and the water run to clear out the lines and holding tanks. Though an old friend at the US EPA had identified a reasonably priced informational oriented analysis package, the turn around time was 4-6 weeks plus the analytical limits were higher than I wanted. I was interested in obtaining a water supply as pristine as possible, thus I would refuse any traces of any industrial compounds. I was specifically looking for solvents, hydrocarbon fuels, heavy metals and pesticide traces. So I determined my best option to verify water quality within the transaction timeframe appeared to be to use an US EPA certified laboratory to perform a rush compliance analysis of the water sample for every primary and secondary contaminants listed under the Safe Drinking Water Act while simultaneously researching the history of the land. The good news is the results confirmed that the on-site drinking water well provided water that met the Safe Drinking Water Standards and was free of trace contaminants beyond the small traces (parts per million) of naturally occurring items such as iron, barium, cooper and moderately hard water (the presence of calcium carbonate). The groundwater supplying the house was uncontaminated. To obtain that analysis within the time frame of the contingency period I spent $1,635.00. The house was the most expensive purchase of my life and I did not want to purchase a house with “bad” water. The water also tasted good. There is no guarantee that the water will remain uncontaminated so I need to monitor it regularly as well as keep an eye out for likely sources of contamination.

2 comments:

While caution in matters of water quality is certainly laudable, I think you're worried where no worry is necessary. Just look at the empirical evidence: The U.S. mandates water quality standards and enforces them; outbreaks of disease due to municipal water quality problems in the U.S are extremely rare. And most significantly, the U.S. population's life expectancy continues to increase.

Rather than spend more money on more restrictive water quality regulations in the U.S., we would do better to address extremely poor water quality in third world nations.

I am afraid I was unclear. I am not advocating more restrictive water quality standards. I am advocating knowledge. I am advocating that private well owners take responsibility for their health and test their water for the 91 substances of concern and knowing the history of their property look further if anything is detected. The costs to test public water supplies for everything constantly is prohibitive. However, people need to understand what acceptable water quality really means. Those of us who obtain their water from public supplies need to be aware of its sources and potential contaminants.

Elizabeth Ward

About Me

Elizabeth was awarded an MBA from the University of Pittsburgh and an MS ChE from Polytechnic Institute of NYU, worked as a chemical engineer for both the US EPA in DC, and at DuPont before working in finance and then becoming consultant with Washington Advisors and is the author of "The Lenders Guide to Developing an Environmental Risk Management Program." Elizabeth retired from Washington Advisors and began her volunteer career and is currently the Treasurer of the Prince William Soil and Water Conservation District.

Purpose

Green Risks provides information to understand the natural world especially in our local region. The blog is a mix of technical guidance and interesting information with a slant towards information to live a greener and more sustainable life. You will find articles on a wide range of water and environmental topics including help with water well problems and maintenance, septic systems and regulations, solar energy, low impact development, and many others all with the intent of teaching practical ways to solve problems and revive common sense in our society.